Inclination indicator for airplanes



jam. l E924' l'ggl J. F. BOORAEM l INCLINATION INDICATOR FOR AIRPLANES Filed June 19, 1919 Patented dan. li, 1F24.

UNITI Affi` inra INCLINATION INDICATOR FOR AIRILANES.

Application led June 19, 1919. Serial No. 305,365.

To all whom t may concern.'

Be it known that I, JOHN FRANCIS Boon- AEM, a citizen of the United States, and a resident of Greenwich, iny the county of lzontal flight when the airplane is flying for- Fairfield and State of Connecticut, have invented certain new and useful Improvements in Inclination Indicators for Airplanes, of which the following is a specification.

The present invention relates to inclination indicators particularly for airplanes and has for an object to-provide a device of this character whichywill indicate the position of the airplane at vall times and in all positions relatively to the earth whether the same is flying upright, upside down or vat an angle oflateral or vertical inclination.

With theseand other objects in view, embodiments of my invention are shown in the accompanying drawings, and these embodiments will be hereinafter more fully described with reference thereto and the invention will be nally pointed out in the claims.

In the accompanying drawings:

Figure 1 is a side elevation of one form of my invention.

Figure 2 is a similar view showing the position of the same when the supporting structure i. e. the airplane, is at an inclination;

Figure 3 is a similar view showing the positionl of the same when the supporting structure is inverted;

Figure 4 is a view partly in section, of a modified form of construction in which baffles are provided interiorily forthe purpose of controlling the action of the indicating means;

Figure 5 is a vertical sectional view of another modified form of construction;

Figure 6 is a side elevation, partly'in section, of the form of the device shown in Figure 4, and with the device inclined and the colored liquid body overlapping the differently colored upper half of the globe, and

Figure 7 is a side elevation of the nested baiiie discs removed from the globe, the view being taken at right angles to Figure 6.

Similar reference characters indicate corresponding parts throughout the several figures of the drawings.

Referring to the drawings and more particularly to Figures 1 to 3 thereof, the embodiment of my invention shown therein comprises a spherical (globe 10 preferably transparent and ferme... er glass, the outer surface being divided into .suitablyvmarked meridian circles,fsaid circles passing through the poles a-b at the ends of the horizontal directional axis parallel to the line of horiwardly in a horizontal line and also passing through the poles of the transverse-axis c at right angles to the same plane. Within the globe there is provided' a hemispherical liquid body 11,

preferably of mercury in a liquid state at' normal temperature, this body adapted by gravity to maintain a constant positionl relatively to the earths center. The upper lhalf of the globe 10 is colored as for instance,

red, and the globev is supported in `suitable fixtures 12 and '13 vmounted upon the fuselage of the airplane. The meridian lines, it will be understood, indicate the degree of deiiection of the airplane and the line of iiying which deviates either way from the horizontal, and as soon as thereis any deviation the edge of the colored portion of the globe at one side of the turning axis will be raised relatively to the upper surface of the body 11 while at the other side it will extend below the upper surface of the body 11 thereby clearly indicating that4 there is an inclination of flight.

the directional axis and in Figure 2 illustrates the position of the device when the airplane is inclined downwardly head on, while Figure 3 illustrates the position when the airplane is inverted as in performing a loop or when flying upside down. It is well known that such upside down iiights may occur without the intention of the fliers and without their realization'that they are flying upside down.

In Figure 4, I have illustrated a modified form of construction in which baiiies are provided within the globe for the purpose of controlling the flow of the liquid body therein so that the position of the liquid body will indicate the mean rather than the extreme positions of the airplane as for instance when swaying or pitching in a gale. These bafiies consist of a plurality of circular plates 14 intersecting the directional axis and alsol a plurality of circular plates 15 intersecting the transverse axis at right angles thereto'` the exterior surface ofthe globe. In FigureA 5 I have illustrated another modified form of construction in which an inner globe 17 is provided within the outer globe 18l forming an annular space therebetween, the said space being bridged by a plurality of baffles 19 and 20. An annular hemisphere 2l of mercury or other suitable liquid is provided within the said space, perforations'QQ in the baiiiesr permitting flow of the liquid throughout the annular space. A light is pron vided withinthe inner sphere.

Fromjtheforegoing it will be seen that my invention contemplates an indicator' which will clearly show at' all timesthe positionof the airplane in an unmistakable' and graphic manner. n y

I have illustrated and described preferred and satisfactory embodiments oi" my invention butit'is obvious that changes may be made therein within the spirit and scope thereof as defined 'in the appended claims.

I claim: v

. l. Anyinclination indicator for airplanes comprisinga hollow spherical transparent globe provided withlmeridian markings, a

plurality of circular plates tted'vvithin said hollow globe and lying in' intersecting planes marked ofi by the meridian lines, said plates provided with openings therethrough, and a liquid body filling substantially the lower lhemisphere'-andad'apted by gravity to maintain a constant position relatively to the earthscent'er; said body being colored.

2. An inclination indicator for airplanes comprising a hollow spherical transparent globe having meridian maf'rkings passing through a horizontal aXisand provided with a suitable colorfon its'upper'he'mispliere, a body of colored liquid Ysupported in` the lower hemis'r'iherel and adapted tol occupy a constant position with respect tof the earths center, and a plurality of Circular plates mounted within said sphere in intersecting planes marked oii by meridian markings on the sphere, said circularplates' having series of openings nearl theiredges to dampen oscillation of the body of liquid. r`

In testimony' that he claims the foregoing as his invention, he' has signed? his na'me' hereunder.

J'. FRANCIS BooRAEM. 

